“The LED may also flash when the E and C leads are switched, but the flash rate will be faster,” Gerbig explained. “This reflects the fact that some types of transistor will operate with their emitter ...

The test voltage is raised to 13.3 V dc again, and VR1 is adjusted so that the transistor turns on. With the upper and lower levels set, the NC point is connected to the circuit (15-V dc charging ...

However, as is sometimes the case, you can replace a complicated circuit by a simple one without much loss of performance. For example, transistors and resistors replace the entire IC (Figure 1). The ...

The LED connects across the output transistor because this approach lets the inductive kickback voltage add to the battery-supply voltage and makes the LED brighter. This circuit operates well from ...

Curious how a solar-powered lamp powers an LED with just a single 1.2-V cell? In a 2012 edition, Elektor presented a clever single-transistor voltage converter circuit by Burkhard Kainka. Let's ...

[Kevin Darrah] wanted to make a simple 3.3V regulator without using an integrated circuit. He wound up using two common NPN transistors and 4 1K resistors. The circuit isn’t going to beat out… ...

A very simple but highly efficient combination lock circuit is shown in the figure. Any type of on/off switches can be used, varying from commercially available inexpensive types to more ...

The transistors were already at the limit of what steady hands and tiny tweezers could handle. So, scientists wanted to make a whole circuit -- the transistors, the wires, everything else they ...